Mesoscopic modelling of charge evolution in conducting polymers

We address here some of the issues relating to conducting polymer based dev ices. We examine the effects of polymer disorder on charge injection, trans port, trapping and recombination in light-emitting diodes (LEDs) using a me soscopic model which includes specific realizations of the electroluminesce nt polymer network. A key point of this model is to consider both the inter molecular and the interdomain charge carrier transport which are strongly i nfluenced by structural polymer disorder. Simulations of bipolar charge evo lution (electrons and holes) through a polydiacetylene (PDA) film, which ar e injected in the polymer layer from the appropriated electrodes, have been used to give some insights to the issue concerning the fraction of polymer molecules contributing to the conduction process as well as to light emiss ion. The effect of charge traps, such as cross-links, on space charge and r ecombination is also discussed. (C) 2000 Elsevier Science B.V. All rights r eserved.